How does one respect Atheists?

An atheist believe that there is no supreme being. An agnostic does not deny the possibility of a supreme being but does not necessarily believe in one. Scientifically speaking, something cannot be considered fact or even theory without some sort of plausible experiment that repeats the same results supporting a hypothesis. But because there is no way to prove whether a supreme being exists or doesn't exist, I think its ridiculously ignorant to consider oneself an Atheist.